Since the days of Isaac Newton, a bedrock principle of physics has been that the basic properties of the universe (the laws of gravity and the speed of light, for instance) are the same in all locations, at all times. So scientists were intrigued by the announcement last August that one of the so-called constants of nature might not be so constant after all.
John Webb, an astronomer at the University of New South Wales in Australia, was studying the fine-structure constant, which governs the strength of the force between charged particles, in a large number of distant galaxies. Using data from the Very Large Telescope in Chile, he and his colleagues found a slight but notable variation in the constant: It increased one part per million for every billion light-years farther they looked. Odder still, an earlier survey in the Northern Hemisphere indicated that the constant decreased with distance, suggesting a possible asymmetry in the universe.
These tentative findings raise the possibility that the physical laws that allow life to exist may hold true only in our particular part of the universe. “There could be regions with different values for the constants of physics,” Webb says. “We inevitably find ourselves in one that allows us to be here.”